Reducing Fractions/Transcript
Transcript Title text reads, The Mysteries of Life with Tim and Moby Tim is reading a book (Nights in the Rodanthe). A box of tissues is nearby. Moby zaps the book with a ray gun. It shrinks to a tiny size. TIM: Hey, I was reading that! Moby zaps the box of tissues. It shrinks, too. TIM: A shrink-ray, huh? Maybe that’ll come in handy for this: A letter appears. Text reads as Tim narrates: Dear Tim and Moby, How do you reduce fractions? From, Zeb. TIM: Let’s see if Moby can answer that. Moby beeps. Tim places a fraction, sixteen twenty-fourths, on the table. Moby zaps the fraction with the shrink-ray. Instead of shrinking in size, the fraction turns into another fraction, two-thirds. Moby checks the shrink-ray and beeps. TIM: What do you mean, it didn’t work? You just reduced a fraction! Reducing a fraction means simplifying it so that the numerator and denominator are both as small as they can possibly be. And the value of the fraction stays the same. Moby beeps. TIM: Well, just to make it as simple as possible! Remember when we ordered that pizza last week? We got the usual: half pepperoni, and half ball-bearings and screws. On-screen, a pizza appears. Half is topped with pepperoni, the other half with ball-bearings and screws. TIM: The pizza had six slices. On-screen, the pizza divides into six equal slices: three pepperoni, and three ball-bearings and screws. TIM: But when we called to order, we didn’t ask for three-sixths pepperoni, and three-sixths metal. We asked for half and half. On-screen, the three slices of pepperoni combine into a half pizza, and the three slices of metal combine into another half pizza. TIM: That’s because three-sixths is the same as one-half! In mathematical terms, they’re equivalent fractions. A label appears, reading, equivalent fractions. An equation reads, three-sixths equals one-half. Moby beeps. TIM: What do you mean, I should stop using pizza to illustrate math concepts? I like pizza. Anyway, to reduce a fraction, you first have to find the greatest common factor of the numerator and the denominator. A label appears, reading, greatest common factor. Moby beeps. TIM: That’s the largest number that will divide evenly into both. Let’s say you’re given the following fraction: twelve-twentieths. On-screen, Tim places the fraction, twelve-twentieths, on the table. TIM: To find the greatest common factor, you can make a list of all the factors of 12 and 20, and then pick the biggest one they have in common. Hey, can you set that thing on, factor? Moby adjusts the shrink-ray and zaps the numerator, 12. A series of numbers appear: 1, 2, 3, 4, 6, and 12. TIM: So the factors of 12 are 1, 2, 3, 4, 6, and 12. Moby zaps the denominator, 20. A series of numbers appear: 1, 2, 4, 5, 10, and 20. TIM: And the factors of 20 are 1, 2, 4, 5, 10, and 20. Looks like the greatest common factor is 4! Moby beeps. TIM: To reduce that fraction, you just divide both the numerator and denominator by their greatest common factor. 12 divided by 4 is 3, so our numerator is 3. An equation appears, reading, 12 divided by 4 equals 3. TIM: And 20 divided by 4 is 5, so our denominator is 5. An equation appears, reading, 20 divided by 4 equals 5. TIM: So twelve-twentieths, reduced to the simplest possible terms, is three-fifths! An equation appears, reading, twelve-twentieths equals three-fifths. TIM: Let’s try it again, with four-fourteenths. A fraction appears, reading, four-fourteenths. TIM: Let’s see. The factors of 4 are 1, 2, and 4, and the factors of 14 are 1, 2, 7, and 14. On-screen, a series of numbers appear by the numerator: 1, 2, and 4. A series of numbers appear by the denominator: 1, 2, 7, and 14. TIM: Looks like the greatest common factor is 2. So the next step is… Moby beeps. TIM: Right: dividing the numerator and the denominator by 2! 4 divided by 2 is 2, and 14 divided by 2 is 7. On-screen, two equations appear, reading, 4 divided by 2 equals 2, and 14 divided by 2 equals 7. TIM: So four-fourteenths reduces to two-sevenths! An equation appears, reading, four-fourteenths equals two-sevenths. Moby beeps. TIM: Well, if there are no common factors, the fraction can’t be reduced; it’s as simple as it’s gonna get. Now can I have my book back? On-screen, Tim holds up the tiny book. Moby beeps. TIM: What do you mean, there’s no enlarging ray? How am I supposed to find out if Adrienne and Paul live happily ever after? Moby beeps. He zaps Tim with the shrink-ray. Tim shrinks to a tiny size. The book is now a normal size in his hand. Tim speaks in a high pitched voice. TIM: Gee, thanks a lot! Crazy robot. Category:BrainPOP Transcripts Category:BrainPOP Math Transcripts